How to tell if Onyx gem is fake?

Question

My boyfriend baught me a lovely temperary engagement/ promise ring and its marked 825 on the inside... is it real silver? it doesnt turn my finger green... it has lil diamonds and a black cubed gem inside.. what is the gem? do you know? is it real, and how to tell?!!! can i wash dishes or take a shower with this ring on? or will it rust or what??

HOW CAN I TELL IF ONYX IS FAKE?

Answer 1

Sometimes dishonest merchants will sell grayish chalcedony or agate that has been dyed black or green to imitate Onyx. Calcite is also sold as Onyx but discerning the two is actually quite easy because Onyx is very hard, but something as soft as a fingernail can scratch Calcite. Also, some marble has been called onyx, but is much softer than onyx and is subject to damage from acids.

Answer 2

Silver is marked 925 , could it be you read as 825? Although there is also a new silver standard that is marked 800 also. If the ring is silver you can wear  in water as silver does not rust.

If it doesnt turn your finger green is a good sign! although this could be true of a silverplate item for sometime until the silver coating wears away to reveal a cheaper alloy underneath.

I can't really tell you what the stones are or if they are real or manmade without seeing, but onyx is a good guess as are lower grade sapphires which appear black and opaque. Both are used for smaller stones and are frequently seen with either silver or 9ct gold.

If you are sure ther diamonds are real then it is likely the stone would be a dark sapphire, it would be pointless for most designers and manufacturers to use diamonds in conjunction with a manmade stone.

Only real way to know is to se the ring through a jewellers loupe at least of 10x strength (like a magnifying glass), if the stones are real they will have inclusions - flaws within them that can be seen in this way. If the stones are pure and clear they are almost 100% manmade - such clarity rarely appears in nature.

A jeweller would probably be able to tell just by simply looking, after handling stones and metals for a while it becomes obvious through a simple glance at colour, sheen etc what might or might not be real.

But i would say also, this is a gift from your new fiancee and you should enjoy it as such - as a ring you say is lovely and given to you out of love :-)